Scores of migrants forced their way into Eurotunnel’s French terminal overnight, clashing with staff and police and causing a temporary suspension of rail services, Eurotunnel said.
The company said traffic levels in the tunnel were back to normal later on Saturday following safety checks, though passenger services were expected to run with delays of up to two hours for the rest of the day.
Roughly 200 migrants entered Eurotunnel’s terminal after midnight by pulling down fencing, with 120 getting into the tunnel before being intercepted inside by French police, the company and police said.
“Such a large group had no chance of reaching the UK, so this was clearly an organised attack aimed at drawing media attention to the desperate situation of the migrants who are stuck in Calais,” Eurotunnel said in a statement.
The police made 23 arrests in clashes that left six injured, after heading off the migrants at a junction between the different tunnels 15 km from the French side.
“This is something new. We have never been faced with something like that. Their determination and aggressiveness are growing,” a police source said.
Police sources have in recent days pointed to the presence at Calais of militants from “No Borders”, a far-left group that opposes border and immigration controls.
Calais has long been an immigration flashpoint but in the past year has become part of a wider pan-European crisis, with states struggling to agree on how to handle inflows of people fleeing conflicts or poverty in the Middle East and Africa.
A tightening of security at the sea port in Calais has prompted increased attempts to access the Channel Tunnel, leading to the deaths of several migrants.
But migrants also targeted the port in a separate incident on Saturday, attempting to jump on lorries queuing on the approach road to the port, a Reuters photographer on site said.
Police intervened to prevent the group, which a police source put at least 300, from entering the port.
The incidents were the latest in a series involving migrants who are camped around the northern port of Calais in the hope of reaching Britain by hiding in lorries and trains.